1. Field of the Invention
The invention relates to the conveying of fluids.
2. Description of the Prior Art
Conveying devices find many applications. One example is disclosed in U.S. Pat. No. 3,923,289 which illustrates a fan for mixing solids and liquids on a continuous basis. A fan rotor is housed in a casing having an inlet opening which is coaxial with the axis of rotation of the fan. Additional inlet openings are provided near the periphery of the casing.
U.S. Pat. No. 5,063,832 shows a blower unit for automobile air conditioners. The unit comprises a scroll casing which accommodates a reversible fan as well as a movable guide for changing the direction of air flow. The guide allows the blower unit to be adapted to automobiles having steering wheels on either the left or the right. The blower unit further comprises an intake device which is designed to admit air into the unit along two mutually perpendicular directions.
U.S. Pat. No. 5,213,469 teaches a sewage pump which is designed to limit the particle size of solids drawn into the pump while allowing stringy material to enter the pump. To this end, the pump has an inlet opening consisting of two spaced oval portions which are connected to one another by an essentially rectangular portion.
There are situations in which it is of advantage to simultaneously draw two or more fluids from different sources. Such a situation exists, for instance, when a gaseous mixture containing combustible components is to be evacuated from an area using a fan driven by an air-cooled motor. Here, it is desirable to draw air from the atmosphere around the motor to cool it and to simultaneously draw out the gaseous mixture while keeping the mixture away from the motor. Thus, the motor constitutes a potential source of ignition for the combustible components of the mixture.
At present, there appears to be no fluid conveying device capable of simultaneously drawing from different fluid sources in a simple manner.